Most major tourist cities offer some form of short-term unlimited pass, typically in 24, 48, 72 hour or weekly flavors, and they come in two distinct types worth separating. Pure transit passes cover unlimited rides on metro, bus, and tram within certain zones and are usually good value if you take more than three or four rides a day. Then there are city tourist cards that bundle transit with museum entry and attraction discounts, which cost much more and only pay off if you genuinely visit several included attractions.
Coverage details matter more than the headline price. Check whether the pass includes airport lines, which are often excluded or need a supplement, whether it covers the zones your hotel sits in, and whether it starts from first validation or from midnight of the purchase day.
Buy from the official operator's app, station machines, or authorized counters, since resellers add markup. And for shorter stays, remember many cities now cap contactless card spending per day, which can quietly beat a tourist pass without any planning.